U.S. patent number 4,376,487 [Application Number 06/227,450] was granted by the patent office on 1983-03-15 for anti-sway, anti-rotation mechanism for crane reeving.
This patent grant is currently assigned to Harnischfeger Corp. of Canada Ltd.. Invention is credited to Stjepan Bagaric, Rostislav Muller, Cornelius J. M. Van Soest.
United States Patent |
4,376,487 |
Van Soest , et al. |
March 15, 1983 |
Anti-sway, anti-rotation mechanism for crane reeving
Abstract
An anti-sway, anti-rotation mechanism for crane reeving
comprises four spaced-apart overhead sheaves on an overhead
support. A lifting beam assembly has four pairs of lifting beam
sheaves. The pairs of lifting beam sheaves are spaced-apart from
each other. A grapple is pivotally connected to the lifting beam
assembly. Cables are connected to the winding drum and extend
between each pair of lifting beam sheaves and two adjacent overhead
sheaves in a V-shaped arrangement to keep the lifting beam assembly
level and prevent the lifting beam assembly from swaying and
rotating, during operation of the crane.
Inventors: |
Van Soest; Cornelius J. M.
(Port Moody, CA), Muller; Rostislav (Port Moody,
CA), Bagaric; Stjepan (Port Moody, CA) |
Assignee: |
Harnischfeger Corp. of Canada
Ltd. (CA)
|
Family
ID: |
22853160 |
Appl.
No.: |
06/227,450 |
Filed: |
January 22, 1981 |
Current U.S.
Class: |
212/274; 212/291;
212/327 |
Current CPC
Class: |
B66C
13/06 (20130101) |
Current International
Class: |
B66C
13/06 (20060101); B66C 13/04 (20060101); B66C
013/06 () |
Field of
Search: |
;212/146-148,220,221,84,127 ;414/735 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
New Zealand Engineering, vol. 30, No. 3, pp. 73-78, Mar. 15,
1975..
|
Primary Examiner: Sheridan; Robert G.
Attorney, Agent or Firm: Townsend and Townsend
Claims
We claim:
1. An anti-sway, anti-rotation mechanism for reeving of a crane
having an overhead support with a winding drum, the mechanism
comprising:
four spaced-apart overhead sheaves on the overhead support, the
winding drum being between two pairs of the overhead sheaves;
a lifting beam assembly with four pairs of lifting beam sheaves,
the pairs of sheaves being spaced-apart from each other;
load carrying means connected to the lifting beam assembly; and
four cables comprising two pairs of adjacent cables extending
downwardly from the winding drum, each cable extending downwardly
and about one said lifting beam sheave of one said pair of lifting
beam sheaves, then upwardly and about an overhead sheave, then
downwardly and about another said lifting beam sheave of another
pair of lifting beam sheaves adjacent said one pair of sheaves,
then upwardly to an end of the cable adjacent the overhead support
to prevent swaying and rotation of the lifting beam assembly during
operation of the crane and to keep the lifting beam assembly
level.
2. A mechanism as claimed in claim 1, each said pair of the lifting
beam sheaves being on an arm of a cross.
3. A mechanism as claimed in claim 2, the cables of each said pair
of cables extending downwardly to different said lifting beam
sheaves on one said arm of the cross, then upwardly to adjacent
said overhead sheaves and then downwardly to lifting beam sheaves
on opposite arms of the cross.
4. A mechanism as claimed in claim 3 comprising means for adjusting
the lengths of the cables.
5. A mechanism as claimed in claim 4, the means for adjusting
comprising four tensioning sheaves rotatably connected to the
overhead support, the cables each extending over one said
tensioning sheave near said end of each cable, and a threaded
connector connecting said end of each said cable to the overhead
support.
6. A mechanism as claimed in claim 1 or claim 5, the lifting beam
assembly having a bottom, the load carrying means being pivotally
connected to the bottom of the lifting beam assembly.
Description
FIELD OF THE INVENTION
This invention relates to an anti-sway, anti-rotation mechanism for
crane reeving.
DESCRIPTION OF THE PRIOR ART
With many loading cranes, for example log handling portal cranes,
it is desirable to lift unbalanced loads with a grapple or to lift
logs, or other items, from the side of a pile. However, if this is
attempted with the standard arrangement of cables and grapple,
several problems arise. An unbalanced load may cause the cables to
deviate from the vertical, possibly allowing the logs or other
material to contact the crane and cause damage. Additionally,
attempting to retrieve logs from the side of a pile with a standard
crane may result in dangerous swinging of the load and entangling
of the cables as the load is lifted. Accordingly, it would be
desirable to provide a mechanism which would permit a crane to lift
an unbalanced load, thus making handling faster, while maintaining
the crane cables vertical. Similarly, it would be desirable to
provide a crane where the logs or other items could be retrieved
from the side of a pile while the cables remain vertical.
In the past, the arrangement of four cables extending downwardly
from a winding drum and passing through four spaced-apart sheaves
on a load carrying frame has been employed for container handling
cranes as seen, for example, in Canadian Pat. No. 679,557 to
Ramsen. However, this arrangement has been used only to keep the
load level and this patent does not disclose a combination which
prevents swaying and rotation, permits the crane to lift an
unbalanced load of logs, or the like, or which permits the crane to
retrieve logs from the side of a storage pile.
SUMMARY OF THE INVENTION
The invention provides an anti-sway, anti-rotation mechanism for
reeving of a crane having an overhead support with a winding drum.
The mechanism comprises four overhead sheaves on the overhead
support, the winding drum being between two pairs of the overhead
sheaves. A lifting beam assembly has four pairs of lifting beam
sheaves, the pairs of sheaves being spaced-apart from each other.
Load carrying means is connected to the lifting beam assembly.
Cables are connected to the winding drum and extend about each said
pair of the lifting beam sheaves and two adjacent said overhead
sheaves in an upwardly opening V-shaped arrangement to prevent
swaying and rotation of the lifting beam assembly during operation
of the crane and keep the lifting beam assembly level.
The invention permits the load carrying means, or grapple, to hang
at an angle with the vertical, as would occur when the grapple is
carrying an unbalanced load or retrieving logs from the side of a
pile, while maintaining the alignment of the cables with the
vertical. Consequently, no dangerous swinging of the load occurs
and there is no additional risk of the load contacting the crane
structure. The speed of handling is accordingly increased, since
there is no need to balance loads for safe handling, and the
grapple can easily retrieve logs, or other material, from a sloping
pile.
BRIEF DESCRIPTION OF THE DRAWINGS
In drawings which illustrate embodiments of the invention:
FIG. 1 is a side elevational view showing an anti-sway,
anti-rotation mechanism, according to an embodiment of the
invention, associated with the trolley of a portal crane;
FIG. 2, appearing after FIG. 4, is a reeving diagram for the
mechanism;
FIG. 3 is a perspective view showing the lifting beam assembly of
the mechanism and the grapple loading from a sloping pile of
logs;
FIG. 4 is a perspective view showing the lifting beam assembly and
the grapple carrying an unbalanced load of logs; and
FIG. 5 is a side elevational view, partly in section, of a device
for adjusting the lengths of cables of the mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The drawings illustrate an anti-sway, anti-rotation mechanism 1 for
cranes. The mechanism 1 is associated with an overhead support, in
this case the trolley 2 of an overhead crane. The mechanism is
suitable for portal-type or rotating-type log handling cranes as
well as other types of overhead cranes. The mechanism includes four
spaced-apart overhead sheaves 4, 6, 8 and 10, each rotatably
connected to the trolley 2. The winding drum 11 is between the pair
of overhead sheaves 4 and 6 and the pair of sheaves 8 and 10.
The mechanism 1 includes a lifting beam assembly 18 which is
cruciform in shape, having four arms 22, 24, 26 and 28, extending
at right angles to each other. The lifting beam assembly 18 has
four pairs of lifting beam sheaves 36, 38, 40 and 42, which are
spaced-apart from each other. Each pair comprises a pair of coaxial
and adjacent lifting beam sheaves rotatably connected to the arms,
for example, outer sheave 37 and inner sheave 39 of pair 36.
A cable basket 46 is connected to the top of lifting beam assembly
18 and its top 48 is adapted to contact the limit switch assembly
50, suspended by cables 52, when the lifting beam reaches it upper
limit.
A load carrying means or grapple 54 is rotatably connected to the
bottom 56 of lifting beam assembly 18, for rotation about vertical
axis 57, by means of the double articulated joint 58. Joint 58 has
a pair of link pins 60 and 62 at right angles to each other to
permit pivoting of grapple 54 about two perpendicular, horizontal
axes. Grapple 54 is a standard type of grapple employing a pair of
cylinders 59 and 61 to open and close a pair of load carrying arms
63 and 64.
The lifting beam assembly 18 is suspended below the trolley 2 by
means of four cable assemblies including a first pair of cables 72
and 74 and a second pair of cables 76 and 78. Cable 72 extends
downwardly from drum 11 towards lifting beam assembly 18 and
extends about the inner sheave of the pair of sheaves 36. From
here, cable 72 extends upwardly and about overhead sheave 8. From
sheave 8, cable 72 extends downwardly and about the inner sheave of
the pair of sheaves 40 which is adjacent pair 36. Cable 72 then
extends upwardly to its end 80 which is connected to trolley 2.
There is an adjusting means or mechanism 84 near the end 80 of
cable 72 for adjusting its length and similar mechanisms for each
of the other cables. As seen in FIG. 5, there is a tensioning
pulley 90 connected to the trolley 2. Cable 72 extends over sheave
90 and is connected to an eye bolt 94 at its end 80 by means of
three rope clips 96 and a thimble 98. Bolt 94 extends through
aperture 100 in retainer 102 at the end of a sleeve 104 which is
connected to the frame 106 of the trolley 2. A nut 108 is
threadedly received on the end of bolt 94, while cotter pin 110 and
lock nut 112 keep nut 108 in place. Bolt 94 and nut 108 provide a
threaded connector connected to the cable 72, whereby the length of
the cable can be adjusted by tightening or loosening nut 108.
Cable 74 extends downwardly from the drum 11 and about the other
sheave of the pair of sheaves 36. From here, cable 74 extends
upwardly and about overhead sheave 4, which is adjacent sheave 8 of
cable 72, and downwardly to the outer sheave of the pair of sheaves
42. From here, cable 74 extends upwardly to its end 114 which is
connected to the trolley by means of one of the adjusting
mechanisms 84.
While cables 72 and 74 both extend downwardly from drum 64 to the
pair of lifting beam sheaves 36, they then extend to different, but
adjacent, overhead sheaves 4 and 8. They then extend downwardly to
opposite pairs of lifting beam sheaves 40 and 42.
The cables 76 and 78 extend downwardly and about the inner sheave
and outer sheave, respectively, of the pair of lifting beam sheaves
38. From pair 38, cable 76 extends upwardly, about overhead sheave
10, downwardly about the outer sheave of the pair of lifting beam
sheaves 40 and then upwardly to its end 116, which is connected to
trolley 2 by means of one of the adjusting mechanisms 84.
From the pair of sheaves 38, cable 78 extends upwardly and then
about overhead sheave 6. From here, cable 78 extends downwardly and
about the inner sheave of the pair of lifting beam sheaves 42. From
here, cable 78 extends upwardly to its end 118 which is connected
to the trolley 2 by means of one of the adjusting mechanisms
84.
In use, the simultaneous winding or unwinding of cables 72, 74, 76
and 78 by drum 11 permits the raising or lowering of lifting beam
assembly 18 while maintaining its level attitude. In this respect,
only, is the invention similar to the arrangement found in the
container handling crane of Canadian Patent 679,557. In the
preferred form of the invention, it should be noted that lifting
beam assembly 18 is suspended from above the pair of lifting beam
sheaves 40 at two-spaced apart points, namely adjacent overhead
sheaves 8 and 10, by portions of cables 72 and 76. A similar
V-shaped arrangement of cables is found at each of the other pairs
of lifting beam sheaves 36, 38, and 42. This V-shaped arrangement
prevents swaying of the lifting beam assembly 18 either along the
axis of drum 11 or in the perpendicular direction.
Referring to FIG. 3, it may be seen how the double articulated
connection 58 permits the grapple 54 to rotate and pivot to pick up
logs from the side of a pile while the lifting beam assembly 18
remains horizontal. Similarly, FIG. 4 illustrates how the grapple
can be held at an angle to hold an unbalanced load of logs, while
the lifting beam assembly 18 again remains level.
* * * * *